The present invention relates to a cylinder head mounting apparatus for internal combustion engines and particularly for V-engines.
Internal combustion engines for outboard motors and the like include one or more cylinder units, each of which includes a cylindrical portion and an outer-head closure portion. Higher horsepower engines employ a plurality of cylinder units arranged as in-line or V-shaped blocks. In both types, the engine is mounted with a plurality of in-line cylinders arranged in a vertical stacked relation. The engine is generally water cooled with an outer water cooling jacket wall integrally cast about the upper portion of the cylinders to define a cooling passageway and chamber about the several cylinders. The head portion is bolted or otherwise secured to the cooling jacket wall with a suitable gasket therebetween to effectively seal the cylinders and the cooling chamber. Generally the head portion will also be water cooled and may conveniently be formed of an inner head and an outer cooling jacket cover secured to the outer surface of the head.
In the V-engines the angular orientation of the vertical aligned cylinder banks develops a reasonably wide engine, particularly where a ninty-degree V is used. Particularly when applied to an outboard motor with the vertical mounting of the engine, the width of the engine becomes significant not only from a constructional standpoint but from an aesthetic consideration. This is particularly true as higher horsepower of outboard motors are developed, generally requiring increased cylinders in each bank. For example although a ninty-degree V-6 engine could for example be designed, the overall height and width is increased significantly with additional cylinders and creates a bulky appearance. Although the engine width can be minimized with a sixty-degree engine block, the available space for a manifold assembly and the like becomes constricted and the width of the engine remains significantly greater than for an in-line engine.